I think we are seeing a new meme. Matt Nowack has taken the awesome HTML5 presentation app in HTML5, which is open source, and has created a presentation discussing jQuery 1.4.
It is good stuff, using the fact that you can embed the features that you want to show. Just as long as you can hit the right arrow to get through the "look at all the people who use jQuery" part (we get it! lots of people use jQuery!)
Salvador Diaz has taken things in another direction. He has ported the HTML5 app to GWT under the hood.
Maybe this presentation app can be the "Java Pet Store" of Ajax libraries :)